// ==========================================================
// CUT Loader
//
// Design and implementation by
// - Floris van den Berg (flvdberg@wxs.nl)
//
// This file is part of FreeImage 3
//
// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
// THIS DISCLAIMER.
//
// Use at your own risk!
// ==========================================================

#include "FreeImage.h"
#include "Utilities.h"

// ----------------------------------------------------------
//   Constants + headers
// ----------------------------------------------------------

#ifdef _WIN32
#pragma pack(push, 1)
#else
#pragma pack(1)
#endif

typedef struct tagCUTHEADER {
    WORD width;
    WORD height;
    LONG dummy;
} CUTHEADER;

#ifdef _WIN32
#pragma pack(pop)
#else
#pragma pack()
#endif

// ==========================================================
// Plugin Interface
// ==========================================================

static int s_format_id;

// ==========================================================
// Plugin Implementation
// ==========================================================

static const char * DLL_CALLCONV
Format() {
    return "CUT";
}

static const char * DLL_CALLCONV
Description() {
    return "Dr. Halo";
}

static const char * DLL_CALLCONV
Extension() {
    return "cut";
}

static const char * DLL_CALLCONV
RegExpr() {
    return NULL;
}

static const char * DLL_CALLCONV
MimeType() {
    return "image/x-cut";
}

static BOOL DLL_CALLCONV
Validate(FreeImageIO *io, fi_handle handle) {
    return FALSE;
}

static BOOL DLL_CALLCONV
SupportsExportDepth(int depth) {
    return FALSE;
}

static BOOL DLL_CALLCONV
SupportsExportType(FREE_IMAGE_TYPE type) {
    return FALSE;
}

static BOOL DLL_CALLCONV
SupportsNoPixels() {
    return TRUE;
}

// ----------------------------------------------------------

static FIBITMAP * DLL_CALLCONV
Load(FreeImageIO *io, fi_handle handle, int page, int flags, void *data) {
    FIBITMAP *dib = NULL;

    if(!handle) {
        return NULL;
    }

    try {
        CUTHEADER header;

        BOOL header_only = (flags & FIF_LOAD_NOPIXELS) == FIF_LOAD_NOPIXELS;

        // read the cut header

        if(io->read_proc(&header, 1, sizeof(CUTHEADER), handle) != sizeof(CUTHEADER)) {
            throw FI_MSG_ERROR_PARSING;
        }

#ifdef FREEIMAGE_BIGENDIAN
        SwapShort((WORD *)&header.width);
        SwapShort((WORD *)&header.height);
#endif

        if ((header.width == 0) || (header.height == 0)) {
            return NULL;
        }

        // allocate a new bitmap

        dib = FreeImage_AllocateHeader(header_only, header.width, header.height, 8);

        if (dib == NULL) {
            throw FI_MSG_ERROR_DIB_MEMORY;
        }

        // stuff it with a palette

        RGBQUAD *palette = FreeImage_GetPalette(dib);

        for (int j = 0; j < 256; ++j) {
            palette[j].rgbBlue = palette[j].rgbGreen = palette[j].rgbRed = (BYTE)j;
        }

        if(header_only) {
            // header only mode
            return dib;
        }

        // unpack the RLE bitmap bits

        BYTE *bits = FreeImage_GetScanLine(dib, header.height - 1);

        unsigned i = 0, k = 0;
        unsigned pitch = FreeImage_GetPitch(dib);
        unsigned size = header.width * header.height;
        BYTE count = 0, run = 0;

        while (i < size) {
            if(io->read_proc(&count, 1, sizeof(BYTE), handle) != 1) {
                throw FI_MSG_ERROR_PARSING;
            }

            if (count == 0) {
                k = 0;
                bits -= pitch;

                // paint shop pro adds two useless bytes here...

                io->read_proc(&count, 1, sizeof(BYTE), handle);
                io->read_proc(&count, 1, sizeof(BYTE), handle);

                continue;
            }

            if (count & 0x80) {
                count &= ~(0x80);

                if(io->read_proc(&run, 1, sizeof(BYTE), handle) != 1) {
                    throw FI_MSG_ERROR_PARSING;
                }

                if(k + count <= header.width) {
                    memset(bits + k, run, count);
                } else {
                    throw FI_MSG_ERROR_PARSING;
                }
            } else {
                if(k + count <= header.width) {
                    if(io->read_proc(&bits[k], count, sizeof(BYTE), handle) != 1) {
                        throw FI_MSG_ERROR_PARSING;
                    }
                } else {
                    throw FI_MSG_ERROR_PARSING;
                }
            }

            k += count;
            i += count;
        }

        return dib;

    } catch(const char* text) {
        if(dib) {
            FreeImage_Unload(dib);
        }
        FreeImage_OutputMessageProc(s_format_id, text);
        return NULL;
    }
}

// ==========================================================
//   Init
// ==========================================================

void DLL_CALLCONV
InitCUT(Plugin *plugin, int format_id) {
    s_format_id = format_id;

    plugin->format_proc = Format;
    plugin->description_proc = Description;
    plugin->extension_proc = Extension;
    plugin->regexpr_proc = RegExpr;
    plugin->open_proc = NULL;
    plugin->close_proc = NULL;
    plugin->pagecount_proc = NULL;
    plugin->pagecapability_proc = NULL;
    plugin->load_proc = Load;
    plugin->save_proc = NULL;
    plugin->validate_proc = Validate;
    plugin->mime_proc = MimeType;
    plugin->supports_export_bpp_proc = SupportsExportDepth;
    plugin->supports_export_type_proc = SupportsExportType;
    plugin->supports_icc_profiles_proc = NULL;
    plugin->supports_no_pixels_proc = SupportsNoPixels;
}
